Search PubMed⌕ Search

Biomedical subjects

F C Wagner

Publications and source records attributed to F C Wagner.

At least 37 records · Page 2Linked to original sources

Traumatic aneurysm of the superior cerebellar artery: case report and review of the literature.

Less than 10% of the 250 reported cases of traumatic intracranial aneurysms have involved the posterior circulation. Traumatic aneurysms of the superior cerebellar artery are extremely rare, with only three cases previously reported. This is the first report of a traumatic superior cerebellar artery aneurysm in which the diagnosis was suggested by computed tomographic scan. The potential for a good outcome suggests the value of early angiography when the history and diagnostic imaging studies suggest the possibility of a traumatic aneurysm.

Adult↗

Effect of nimodipine-associated hypotension on recovery from acute spinal cord injury in cats.

The effect of nimodipine on acute spinal cord trauma was studied in cats. Spinal evoked responses (SERs) were abolished after weight drop injury of 100 g-cm. All control animals showed spontaneous recovery of spinal cord function as measured by SERs. Treatment with a moderate intravenous dose of nimodipine resulted in a 32% drop in systemic blood pressure and delay in or failure of spinal cord recovery. We concluded that in this model, nimodipine treatment had deleterious effect on the spinal cord recovery due to the significant associated hypotension. It is likely that marked hypotension in the case of traumatic loss of autoregulation overrides the expected nimodipine-related increase in spinal cord blood flow with resultant additional ischemic damage.

Acute Disease↗

Effect of lidocaine treatment on acute spinal cord injury.

The effect of continuous infusion of lidocaine on acute spinal cord trauma in cats was studied. Intravenous and subarachnoid administration of lidocaine did not alter generation and conduction of the spinal evoked responses (SERs) in intact animals. The cortical somatosensory evoked responses and SERs were abolished after weight drop injuries of 120 and 400 g-cm. No return of the evoked responses occurred within 4 hours after trauma in either the lidocaine- or the saline-treated groups. Loss of SERs and appearance of an evoked injury potential were sensitive determinants of spinal cord injury. We concluded that lidocaine treatment did not facilitate the return of spinal cord function in this model of acute spinal cord injury.

Animals↗

Digital angiographic quantification of blood flow dynamics in embolic stroke treated with tissue-type plasminogen activator.

Computer analysis of digital subtraction angiography (DSA) was utilized to quantify the effectiveness of tissue-type plasminogen activator (TPA) in a rabbit cerebroembolic stroke model. Fourteen animals underwent cannulation of the facial artery and a preembolus angiogram. Autologous blood clots were then injected, and occlusion of the internal carotid artery at the circle of Willis was documented with repeat angiogram. The experimental group received a 1-mg/kg intravenous infusion of TPA via a femoral catheter for 90 minutes. A control group received an equivalent volume of saline. Follow-up angiograms were performed every 15 minutes. The TPA-treated animals showed progressive improvement in flow through previously occluded vessels. Time-density curves of the contrast material over the middle cerebral artery trunk and brain parenchyma were generated. The best integrated curves for the two groups were compared at 30 minutes after occlusion and 90 minutes after treatment. Animals were then observed for 24 hours and their neurological status was documented. Premortem infusion of either Evans blue dye or neutral red dye was performed and the integrity of the blood-brain barrier and tissue perfusion were assessed by video planometry. Significant improvements were noted by DSA, and Evans blue and neutral red dye studies in animals treated with TPA.

Animals↗

Intraoperative sonographic monitoring of reduction of thoracolumbar burst fractures.

Intraoperative real-time sonography was used to monitor surgical reduction of acute thoracolumbar burst fractures in eight patients. Real-time sonography was performed after laminectomy through a saline-filled operative field using either a 5.0 or a 7.5 MHz transducer. Sonography was performed during Harrington rod distraction and during fracture reduction to confirm adequacy of decompression of the spinal canal. This technique is useful to monitor surgery and in defining adequate fracture reduction.

Adult↗

Methylprednisolone and neurological function 1 year after spinal cord injury. Results of the National Acute Spinal Cord Injury Study.

A multi-center double-blind randomized clinical trial was conducted by the National Acute Spinal Cord Injury Study Group to examine the efficacy of high-dose methylprednisolone (1000-mg bolus and 1000 mg daily thereafter for 10 days) compared with that of a standard dose (100-mg bolus and 100 mg daily for 10 days). No significant difference was observed in neurological recovery of motor function, pinprick response, or touch sensation 1 year after injury between the two treatment groups, after adjustment for other potentially confounding factors. Analyses that specifically took into account the patients' total steroid dose and relative weight confirmed the lack of a steroid treatment effect. The case fatality rate was 10.7% during the 1st year after injury, and this was not associated with the steroid treatment protocol or the patient's gender. Deaths did occur significantly more frequently among patients who were completely (15.3%) and partially (8.6%) plegic than among those who were paretic (2.5%, p = 0.0005), and among patients aged 50 years or older (38.6%, p = 0.0001).

Clinical Trials as Topic↗

The Manx cat as an animal model for neurogenic vesical dysfunction associated with myelodysplasia: a preliminary report.

The Manx cat breeds consistently for spinal dysraphism (myelodysplasia) and has spinal cord neuropathologic abnormalities similar to those of myelodysplastic humans. The results of detailed urodynamic and histochemical evaluation of 1 Manx kitten and limited anatomic study of another Manx kitten are described. Urodynamic evaluation revealed significant abnormalities of vesicourethral function: detrusor areflexia, autonomous pressure response to bladder filling, a dysfunctional proximal urethra and poor quality pelvic floor electromyographic activity. Of particular interest, catecholaminergic histochemical studies of the bladder and urethra demonstrated a complete absence of adrenergic fibers, even in the trigone area where they are reported to be abundant. This finding correlated with the urodynamic dysfunction of the proximal urethra. Cholinergic histochemical studies were normal. Examination of the spinal cord revealed moderate hydromyelia throughout the entire length of the cord. The similarities of normal vesicourethral function in man and the cat and our preliminary findings of vesicourethral dysfunction in the Manx cat suggest that this animal may be a particularly valuable model for further research.

Adrenergic Fibers↗

Delayed post-traumatic extracerebral hematomas.

Acute craniocerebral trauma remains a difficult management problems. Optimal conditions for recovery require stabilization of vital signs, removal of a mass lesion when present, and control of intracranial pressure. While computerized tomography (CT) has helped achieve these objectives, there remain patients who may develop a second extracerebral hematoma not evident on their initial preoperative scan. This report concerns our experience with patients who developed such delayed post-traumatic extracerebral hematomas shortly after evacuation of hematomas at other sites. Between 1 January 1979 and 1 October 1980, 47 patients underwent emergency evacuation of a traumatic extracerebral hematoma (38 acute subdural and 18 acute epidural hematomas) at the Yale New Haven Hospital. Within 24 hours, four patients developed, in addition, a total of six delayed extracerebral hematomas (10%) which also required evacuation. In all of these patients a skull fracture was present at the site of the delayed hematomas. This experience suggests: 1) Exploration of extracerebral space beneath a skull fracture should be considered following evacuation of a hematoma at another site. 2) Repeat CT is indicated if anticipated improvement does not occur after evacuation of a hematoma. 3) Decompression of the intracranial contents by removal of a hematoma may promote the development of another delayed hematoma.

Adult↗

Early decompression and neurological outcome in acute cervical spinal cord injuries.

To evaluate the effect on neurological outcome of spinal core compression persisting after a closed injury, the authors reviewed 44 of 62 consecutively managed cases of cervical spinal cord and spine injuries at C3-7, inclusive. Decompression within 48 hours of injury confirmed by myelography or open reduction. Neurological status, graded numerically on a spinal trauma scale at admission and at follow-up review (an average of 1 year +/- 2 months after admission), and precent recovery of neurological deficit were compared to canal narrowing (22 severe, greater than or equal to 30%, versus 22 moderate, 11% to 29%; or mild, less than or equal to 10%) and to delay before treatment (30 within 8 hours of injury versus 14 treated 9 to 48 hours after injury). Severe narrowing was equated with compression. Status at admission and at follow-up review was positively correlated. Patients with admission scores of less than 2 recovered a mean of 15% of their deficit, while those with scores more than 2 recovered a mean of 77%. Admission status correlated significantly with spinal canal narrowing but not with vertebral body displacement. Time of treatment had no significant effect upon admission status and percent recovery. No significant difference in the percent of recovery was noted, whether decompression was early (up to 8 hours) or late (9 to 48 hours) after injury. Surgery did not significantly alter the percent of recovery. The findings indicate that the initial injury to the cervical spinal cord and spine remains the primary determinant of neurological outcome. Severe canal narrowing with cord compression thereafter appears to have comparatively little effect. The conclusion that decompression is without effect is not possible without comparison with a group of patients whose spinal canals remained narrowed at follow-up review.

Adolescent↗

A scale for evaluation of spinal cord injury.

A scale has been developed for assessment of the severity of spinal cord injury and the prognosis for recovery. Based on neurological examination, this scale employs numerical grading of selected functions below the level of the injury. The scale is adaptable to prospective as well as retrospective studies, and provides a reliable estimation of prognosis and, therefore, a means of comparing the effectiveness of differing treatment modalities. In relation to a group of 37 patients with cervical spinal cord injury treated under one protocol and assessed within 24 hours and again at 1 year from injury, a descriptive model of the patterns of recovery has been obtained. Relative recovery of the initial deficit measured as a "percentage recovery ratio" is presented as an analytical tool for comparison of effectiveness of different methods of therapy.

Analysis of Variance↗

Intracranial pressure in nontraumatic ischemic and hypoxic cerebral insults.

Intracranial pressure (ICP) and cerebral perfusion pressure were monitored in 12 patients who were comatose secondary to hypoxic (five cases) or hypotensive (seven cases) nontraumatic cerebral insults. Patients who were hypotensive but not hypoxic developed significant increased ICP. In patients who were comatose from hypoxic cerebral insults without hypotension, ICP was normal. When an increase in ICP was diagnosed, patients were managed aggressively so as to improve cerebral perfusion and lower ICP. Although a functional salvage rate of 25% was obtained, this may reflect the severity of the initial cerebral insult rather than the effect of treatment. In order to prevent the potential deleterious effects of raised ICP, it is concluded that monitoring ICP and maintaining adequate perfusion may be warranted in comatose patients who have suffered nontraumatic diffuse ischemic but not purely hypoxic cerebral insults.

Adolescent↗

Effect of trauma dose on spinal cord edema.

The spinal cord of anesthetized cats was subjected to impact trauma of different intensities to determine how changes in trauma magnitude affect the formation and distribution of edema. All animals underwent a laminectomy to expose the cord segments corresponding to the T5--7 vertebrae. Fourteen cats were injected with fluorescein-labeled albumin, and then subjected to 260, 360, 500, or 700 gm-cm injury to the spinal cord. They were sacrificed at 8 hours after trauma. Twelve cats were injected with fluorescein-labeled dextrans of 20,000, 40,000, 70,000, or 150,000 molecular weight (MW) prior to 500 gm-cm injury, and sacrificed 8 hours after trauma. Serial cord sections from both groups were studied by fluorescence microscopy. In nine cats, sections of cord were removed 8 hours after trauma of 260, 360, or 500 gm-cm impact, and 1-cm sections were assayed for dry weight. Extravasated tracers were present in areas of hemorrhage at the site of impact in all animals. Extension of tracers and increases in tissue water rostrally and caudally from the site of impact were observed consistently with time only in animals receiving 500 or 700 gm-cm trauma. The distance of migration was similar for all tracers. The longitudinal distribution of increased tissue water was consistent with the distribution of fluorescein markers. The findings indicate that the longitudinal extension of posttraumatic edema is directly related to the amount of initial trauma.

Albumins↗